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泛型依赖注入

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1. bean层

   package com.atguigu.bean;public class Book {     }

   package com.atguigu.bean;public class User {     }

2. dao层

   package com.atguigu.dao;import org.springframework.stereotype.Repository;/** * 定义了各种 增删改查方法 * * @param 
        
          */@Repositorypublic abstract class BaseDao
         
           {     	public abstract void save();	}
         
        

   package com.atguigu.dao;import org.springframework.stereotype.Repository;import com.atguigu.bean.Book;@Repositorypublic class BookDao extends BaseDao
        
         {     	@Override	public void save() {     		System.out.println("保存图书");	}	}
        

   package com.atguigu.dao;import org.springframework.stereotype.Repository;import com.atguigu.bean.User;@Repositorypublic class UserDao extends BaseDao
        
         {     	@Override	public void save() {     		System.out.println("保存用户");	}}
        

3. service层

   //子类继承了父类，就相当于子类拥有了父类的属性与方法，尽管父类没有创建bean对象，但是因为子类创建了bean对象，所以在注入属性时会根据子类的的泛型注入属性。package com.atguigu.service;import org.springframework.beans.factory.annotation.Autowired;import com.atguigu.dao.BaseDao;public class BaseService
        
          {     	@Autowired	BaseDao
         
           baseDao;		public void save(){     		System.out.println("自动注入"+baseDao);		baseDao.save();	}	}
         
        

   package com.atguigu.service;import org.springframework.stereotype.Service;import com.atguigu.bean.Book;@Servicepublic class BookService extends BaseService
        
         {     }
        

   package com.atguigu.service;import org.springframework.stereotype.Service;import com.atguigu.bean.User;@Servicepublic class UserService extends BaseService
        
         {     }
        

4. 测试

   package com.atguigu.test;import static org.junit.Assert.*;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.atguigu.service.BookService;import com.atguigu.service.UserService;import com.sun.xml.internal.bind.CycleRecoverable.Context;public class IOCTest {     	ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");		@Test	public void test() {     		BookService bookService = context.getBean("bookService",BookService.class);		UserService userService = context.getBean("userService",UserService.class);				bookService.save();		userService.save();        /*        	自动注入com.atguigu.dao.BookDao@76329302            保存图书            自动注入com.atguigu.dao.UserDao@5e25a92e            保存用户        */		//		Spring中可以使用带泛型的父类类型来确定子类类型		System.out.println(bookService.getClass().getGenericSuperclass());//		com.atguigu.service.BaseService
        
         	}}
        

   System.out.println(bookService.getClass().getGenericSuperclass());

   // com.atguigu.service.BaseService<com.atguigu.bean.Book>

   }

   }